FDFilterGen.cxx

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/*
 * Copyright (c) 2001-2004 MUSIC TECHNOLOGY GROUP (MTG)
 *                         UNIVERSITAT POMPEU FABRA
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include "FDFilterGen.hxx"
#include "CLAM_Math.hxx"
#include <iostream>

#define MINUSINFINITY -99 //Value for an infinitely negative number

namespace CLAM {
        void FDFilterGenConfig::DefaultInit(void)
        {
                AddAll();
                UpdateData();

                SetGain(0);

                SetHighCutOff(0);
                SetLowCutOff(0);

                SetPassBandSlope(0);
                SetStopBandSlope(0);

                SetSpectralRange(22050); //default value for consistency between classes
                
        }

        FDFilterGen::FDFilterGen( const FDFilterGenConfig& c)
                : Output("Output",this)
                , Gain("Gain",this, &FDFilterGen::UpdateControlChangedFlag)
                , HighCutOff( "High Cutoff Frecuency",this, &FDFilterGen::UpdateControlChangedFlag)
                , LowCutOff( "Low Cutoff Frecuency",this, &FDFilterGen::UpdateControlChangedFlag)
                , PassBandSlope("Pass Band Slope",this, &FDFilterGen::UpdateControlChangedFlag)
                , StopBandSlope( "Stop Band Slope",this, &FDFilterGen::UpdateControlChangedFlag)
                , SpectralRange(0)
                , Type( EFDFilterType::eLowPass )
                , mControlChanged( false )
        { 
                Configure(c); // here all controls are initialized
        };


        
        bool FDFilterGen::ConcreteConfigure(const ProcessingConfig& c)
        {
                CopyAsConcreteConfig(mConfig, c);

                mControlChanged=true; //we want the next Do to perform an action
                if (mConfig.HasSpectralRange())
                        SpectralRange=mConfig.GetSpectralRange();
                if (mConfig.HasGain())
                        Gain.DoControl(mConfig.GetGain());
                if (mConfig.HasHighCutOff())
                        HighCutOff.DoControl(mConfig.GetHighCutOff());
                if (mConfig.HasLowCutOff())
                        LowCutOff.DoControl(mConfig.GetLowCutOff());
                if (mConfig.HasPassBandSlope())
                        PassBandSlope.DoControl(mConfig.GetPassBandSlope());
                if (mConfig.HasStopBandSlope())
                        StopBandSlope.DoControl(mConfig.GetStopBandSlope());
                if (mConfig.HasType())
                        Type=mConfig.GetType();
                
                
                return true;
        }
  
        void FDFilterGen::UpdateControlChangedFlag(TControlData val)
        {
                mControlChanged=true;
        }
        
        
        bool FDFilterGen::Do()
        {
                return 0;
        }
        
        bool FDFilterGen::Do(Spectrum &out)
        {
                // Only do something after have received an incontrol.
                if (!mControlChanged) return false;
                mControlChanged=false; 
                
    // Instantiate the BPF buffer of the spectrum if necessary.
                out.AddMagBPF();
                out.AddPhaseBPF();
                if (out.UpdateData()) {
                        out.SetBPFSize(10);
                }
                else if (out.GetBPFSize()<10) 
                        out.SetBPFSize(10);
                
                
                EScale originalScale = out.GetScale();
                out.SetScale(EScale(EScale::eLog));
                
                TData g,flc,fhc,spb,ssb,fsr;
                g=Gain.GetLastValue();
                flc=LowCutOff.GetLastValue();
                fhc=HighCutOff.GetLastValue();
                spb=PassBandSlope.GetLastValue();
                ssb=StopBandSlope.GetLastValue();
                fsr=SpectralRange;
                
                // Legend:
                // g      stands for Gain
                // flc    stands for Lower cutoff frequency
                // fhc    stands for Higher cutoff frequency
                // spb    stands for Slope for the pass band
                // ssb    stands for Slope for the stop band
                // fsr    stands for Sampling Rate Frequency 

                switch((int)Type)
                        {
                        case EFDFilterType::eLowPass:
                        {
                                // We add four points to the BPF ( the four control points for the filter )
                                out.SetBPFSize(4); 
                                
                                TData fsr_by_flc = fsr/flc;

                                SetFilterPoint(out,0,0,g);
                                SetFilterPoint(out,1,flc*CLAM_pow(2.0,-3.0/ssb),g);
                                SetFilterPoint(out,2,flc,g-3);
                                SetFilterPoint(out,3,fsr,g-3-ssb*(log(fsr_by_flc)/log(TData(2))));
                                break;
                        }
                        case EFDFilterType::eHighPass:
                        {
                                out.SetBPFSize(4);
                                SetFilterPoint(out,0,0,MINUSINFINITY);
                                SetFilterPoint(out,1,fhc,g-3);
                                SetFilterPoint(out,2,fhc*CLAM_pow(2.0,3.0/spb),g);
                                SetFilterPoint(out,3,fsr,g);
                                break;
                        }
                        case EFDFilterType::eBandPass:
                        {
                                out.SetBPFSize(6);
                                SetFilterPoint(out,0,0,MINUSINFINITY);
                                SetFilterPoint(out,1,flc,g-3);
                                SetFilterPoint(out,2,flc*CLAM_pow(2.0,3.0/spb),g);
                                SetFilterPoint(out,3,fhc*CLAM_pow(2.0,-3.0/ssb),g);
                                SetFilterPoint(out,4,fhc,g-3);
                                SetFilterPoint(out,5,fsr,MINUSINFINITY);
                                
                                break;
                        }
                        case EFDFilterType::eStopBand:
                        {
                                out.SetBPFSize(7);
                                SetFilterPoint(out,0,0,g);
                                SetFilterPoint(out,1,flc*CLAM_pow(2.0,-3.0/ssb),g);
                                SetFilterPoint(out,2,flc,g-3);
                                TData crossFreq=(CLAM_pow((double)flc,(1.0/(1.0-spb/ssb)))/CLAM_pow((double)fhc,(1.0/(ssb/spb-1.0))));
                                TData crossf_by_flc = crossFreq/flc;
                                SetFilterPoint(out,3,crossFreq,g-3-ssb*(log(crossf_by_flc)/log(TData(2))));
                                SetFilterPoint(out,4,fhc,g-3);
                                SetFilterPoint(out,5,fhc*CLAM_pow(2.0,3.0/spb),g);
                                SetFilterPoint(out,6,fsr,g);
                                break;
                        }

                        }
                if (originalScale==EScale::eLinear)
                {       
                        int bpfSize=out.GetBPFSize();
                        BPF& bpf=out.GetMagBPF();
                
                        for (int i=0; i<bpfSize; i++) {
                                
                                TData tmpValue = bpf.GetValueFromIndex(i);
                                                
                                tmpValue = (tmpValue==0.0001) ? 0 : CLAM_pow(10.0,tmpValue/20.0); 
                                bpf.SetValue(i, tmpValue);
                        }
                        out.SetScale(EScale(EScale::eLinear));
                }

                return true; 
        }
        
        void FDFilterGen::SetFilterPoint(Spectrum& out,TIndex pos,TData freq,TData mag,TData phase)
        {
                out.GetMagBPF().SetValue(pos, mag);
                out.GetMagBPF().SetXValue(pos,freq);
                out.GetPhaseBPF().SetValue(pos,phase);
                out.GetPhaseBPF().SetXValue(pos,freq);
        }
        
}